qHAADF is based on the analysis of
normalized integrated intensities by a method developed by Sergio I. Molina of
University of Cadiz. From the automatic finding of intensity peaks, the method
measures integrated intensities in selected areas corresponding to projected
atomic columns. From these intensities, based on either the use of experimental
HAADF images taken from calibrated samples or areas from the sample with known
composition, compositions of each atomic column are obtained and mapped.

In addition to this function, another
remarkable possibilities of this software are the efficient finding and mapping
of interstitial atoms in materials, the counting of atoms in each analyzed
atomic column, and the estimation of column-to-column compositional maps in
materials by using simulated HAADF images as a reference for this
determination. The combined use of qHAADF with PPA (Peak
Pairs Analysis) software constitutes a powerful tool for the analysis of both
the strain and composition of materials with sub-nanometer spatial
resolution.@

About HREM Research Inc.

Founded in 2001, HREM Research Inc.
specializes in developing products and services that enhance High-Resolution
Electron Microscopy (HREM). Dr. Kazuo Ishizuka, the founder of a company has
established the whole technique for HREM image simulation. Thus, a company's
flagship product, Mac/WinHREM, is a world leading
HREM image simulation software. Currently, HREM Research Inc. is actively
working on making useful techniques to be available for the HREM community. For
more information, visit http://www.hremresearch.com or contact support@hremresearch.com.

Contact:

Kazuo Ishizuka

HREM Research Inc.

14-48 Matsukazedai, Higashimatsuyama

355-0055 JAPAN

Supplementary materials

(Left) Map of normalized integrated intensities measured
from a HAADF-STEM image of a double InAs-GaAs
epitaxial layer. These intensities are directly related to the composition in
each atomic column of the material.

(Right) Map of Bi content
(expressed as number of atoms) in each atomic column of a GaAs1-xBix
epitaxial layer, which has been obtained from the analysis of integrated
intensities of HAADF images.